Lithium based batteries are made from a large number of materials in which the cathode may be a lithium intercalating oxide or phosphate (nanoparticles) and the anode may be lithium metal or carbon or lithium titanium oxide. A lithium ion conducting electrolyte is provided between the anode and cathode. The lithium ion conducting electrolyte is generally an organic, ion-conducting liquid at ambient temperatures allowing power to be output on demand—i.e. the battery is “active.” Reserve batteries are batteries which require activation before being able to output power. Reserve batteries may be activated by injecting a liquid electrolyte into the space between the anode and cathode before use. The activation may include breaking a separately partitioned ampoule full of electrolyte.